1. Field of the Invention
The present embodiments relate to methods, systems, and programs for allocating resources in a networked storage system, and more particularly, methods, systems, and computer programs for scheduling the use of resources using multiple schedulers to improve quality of service (QoS) in storage systems.
2. Description of the Related Art
Network storage, also referred to as network storage systems or storage systems, is computer data storage connected to a computer network providing data access to heterogeneous clients. Typically network storage systems process a large amount of Input/Output (10) requests, and high availability, speed, and reliability are desirable characteristics of network storage. In addition to processing read and write IO requests, network storage systems need to perform other background operations required for maintaining these systems, such as garbage collection of obsolete data and compaction of data (e.g., merging contents of two half-filled segments into one full segment), creating snapshots of data, backup and replication procedures, etc.
However, if a network storage device spends most of its time processing read and write IOs, the background operations may not run efficiently, which in the long run will affect the performance and reliability of a network storage device. On the other hand, if background operations consume too many processing resources (e.g., CPU cycles) of the storage system, read and write IO performance will be degraded.
What is needed is a network storage device, software, and systems that provide for fair utilization of system resources to enable a storage system to process IOs with high performance, while reserving enough resources to perform background operations required for the ongoing operation of the network storage device.
It is in this context that embodiments arise.